Remove .NET Framework remarks (System.Net.*)

[gewarren]

.NET Framework API ref has moved to its own repo (https://github.com/dotnet/dotnetfw-api-docs), so we can clean up .NET Framework remarks, exceptions, and code examples out of this repo. Contributes to #12513.

Removes remarks and examples related to:

• .NET Framework versions
• Code-access security
• Configuring apps via app.config file
• App domains

Also remarks all remarks from obsolete APIs.

Hide whitespace changes

[Copilot]

Pull request overview

This PR updates the .NET API reference XML docs under System.Net.* to remove .NET Framework-specific remarks, links, and guidance (for example, dotnet/framework articles, CAS/config/app.config notes, and implementation-difference callouts) now that .NET Framework API reference docs live in a separate repository.

Changes:

• Removes .NET Framework-specific remarks/notes/related links across Sockets, Security, Mail, Http, Cache, and NetworkInformation APIs.
• Simplifies or rewrites several remarks/exceptions to be framework-agnostic (or removes them entirely).
• Cleans up markdown formatting/whitespace in multiple XML <format type="text/markdown"> blocks.

Reviewed changes

Copilot reviewed 31 out of 33 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
xml/System.Net.WebSockets/WebSocket.xml	Tweaks obsolete attribute message to remove “.NET Framework” wording.
xml/System.Net.Sockets/TcpListener.xml	Removes .NET Framework network-tracing notes from remarks/examples.
xml/System.Net.Sockets/TcpClient.xml	Removes .NET Framework notes; restructures several remarks blocks.
xml/System.Net.Sockets/SocketFlags.xml	Minor whitespace cleanup around examples section.
xml/System.Net.Sockets/SocketAsyncEventArgs.xml	Removes .NET Framework related-article links and tracing note.
xml/System.Net.Sockets/Socket.xml	Removes .NET Framework related-article links, tracing notes, and framework-only exception wording.
xml/System.Net.Sockets/IPProtectionLevel.xml	Cleans markdown formatting and removes a .NET Framework config-doc related link.
xml/System.Net.Security/SslStream.xml	Updates remarks to reduce .NET Framework-specific guidance and rewords caching notes.
xml/System.Net.Security/SslClientAuthenticationOptions.xml	Removes .NET-version conditional wording for AuthenticateAsClient usage.
xml/System.Net.PeerToPeer/PnrpPermissionAttribute.xml	Removes CAS/.NET Framework-era explanatory remarks and leaves placeholders.
xml/System.Net.PeerToPeer/PnrpPermission.xml	Removes CAS/.NET Framework-era remarks/seealso/related links and leaves placeholders.
xml/System.Net.PeerToPeer.Collaboration/PeerCollaborationPermissionAttribute.xml	Removes CAS/.NET Framework-era explanatory remarks and leaves placeholders.
xml/System.Net.PeerToPeer.Collaboration/PeerCollaborationPermission.xml	Removes CAS/.NET Framework-era remarks and leaves placeholders.
xml/System.Net.NetworkInformation/Ping.xml	Removes .NET Framework related-article links.
xml/System.Net.NetworkInformation/PhysicalAddress.xml	Removes .NET Framework/.NET 5+ conditional formatting notes from remarks.
xml/System.Net.NetworkInformation/NetworkInformationPermissionAttribute.xml	Removes CAS/.NET Framework-era explanatory remarks and leaves placeholders.
xml/System.Net.NetworkInformation/NetworkInformationPermission.xml	Removes CAS/.NET Framework-era explanatory remarks and leaves placeholders.
xml/System.Net.NetworkInformation/NetworkChange.xml	Minor whitespace cleanup around examples section.
xml/System.Net.Mail/SmtpPermissionAttribute.xml	Removes CAS/.NET Framework-era explanatory remarks and leaves placeholders.
xml/System.Net.Mail/SmtpPermission.xml	Removes CAS/.NET Framework-era explanatory remarks and leaves placeholders.
xml/System.Net.Mail/SmtpClient.xml	Removes .NET Framework config-file guidance and related links; simplifies remarks.
xml/System.Net.Mail/SmtpAccess.xml	Replaces detailed remarks/examples with placeholder remarks.
xml/System.Net.Mail/MailMessage.xml	Removes .NET Framework config-file remark; updates “Framework” wording.
xml/System.Net.Http/WinHttpHandler.xml	Removes .NET Framework-specific trailing-headers behavior notes.
xml/System.Net.Http/SocketsHttpHandler.xml	Simplifies default-value wording to remove version-specific callout.
xml/System.Net.Http/HttpResponseMessage.xml	Removes .NET Framework-specific disposal behavior note; keeps guidance on status handling.
xml/System.Net.Http/HttpClientHandler.xml	Removes .NET Framework/Core behavioral differences and related exceptions.
xml/System.Net.Http/HttpClient.xml	Removes per-implementation timeout differences and simplifies exception docs.
xml/System.Net.Cache/RequestCachePolicy.xml	Removes config-file guidance and trims examples/remarks accordingly.
xml/System.Net.Cache/RequestCacheLevel.xml	Removes .NET Framework machine.config mention and related link; adjusts summary text.
xml/System.Net.Cache/HttpRequestCachePolicy.xml	Removes config-file guidance and trims examples/remarks accordingly.
xml/System.Net.Cache/HttpRequestCacheLevel.xml	Removes config-file/machine.config mention and related link; adjusts summary text.
xml/System.Net.Cache/HttpCacheAgeControl.xml	Minor whitespace cleanup and wording change to remove “Framework will” phrasing.

Comments suppressed due to low confidence (7)

xml/System.Net.Sockets/TcpClient.xml:1040

• The second NOTE marker (> [!NOTE]) was accidentally appended to the end of the preceding NOTE line, which breaks the markdown note block rendering. Put the second > [!NOTE] on its own line (or remove it if it's meant to be a continuation of the same note).
  xml/System.Net.Sockets/TcpClient.xml:1245
• The second NOTE marker (> [!NOTE]) was accidentally appended to the end of the preceding NOTE line, which breaks the markdown note block rendering. Put the second > [!NOTE] on its own line (or remove it if it's meant to be a continuation of the same note).
  xml/System.Net.Sockets/TcpClient.xml:1313
• The second NOTE marker (> [!NOTE]) was accidentally appended to the end of the preceding NOTE line, which breaks the markdown note block rendering. Put the second > [!NOTE] on its own line (or remove it if it's meant to be a continuation of the same note).
  xml/System.Net.Sockets/TcpClient.xml:1370
• The second NOTE marker (> [!NOTE]) was accidentally appended to the end of the preceding NOTE line, which breaks the markdown note block rendering. Put the second > [!NOTE] on its own line (or remove it if it's meant to be a continuation of the same note).
  xml/System.Net.Sockets/TcpClient.xml:1492
• The second NOTE marker (> [!NOTE]) was accidentally appended to the end of the preceding NOTE line, which breaks the markdown note block rendering. Put the second > [!NOTE] on its own line (or remove it if it's meant to be a continuation of the same note).
  xml/System.Net.Sockets/TcpClient.xml:1552
• The second NOTE marker (> [!NOTE]) was accidentally appended to the end of the preceding NOTE line, which breaks the markdown note block rendering. Put the second > [!NOTE] on its own line (or remove it if it's meant to be a continuation of the same note).
  xml/System.Net.Security/SslStream.xml:432
• Grammar: "an anonymous sessions" should be singular ("an anonymous session").

> [!NOTE]
> .NET caches SSL sessions as they are created and attempts to reuse a cached session for subsequent requests, if possible. When attempting to reuse an SSL session, .NET uses the first element of the <xref:System.Security.Cryptography.X509Certificates.X509Certificate2Collection> provided during authentication (if there is one), or tries to reuse an anonymous sessions if the certificate collection is empty.

[ManickaP]

Are we intentionally removing info about older, not supported .NET versions? I mean older .NET Core, .NET 5 etc.? Or is it getting moved else where? And I'm not talking about framework.
cc @dotnet/ncl

[gewarren]

That's a good question. This was probably a mistake, but maybe we don't need to publish API ref for out of support .NET Core versions anymore. I'll investigate.

[gewarren]

Jan Kotas thinks we can remove docs for out of support .NET Core versions. I logged #12648.